Home automation is a catchall phrase for xe2x80x9csmartxe2x80x9d low voltage and high voltage electrical appliances in a home. In its simplest form, it may be an outdoor light with a motion detector. In a more complex form, it may be a totally integrated home electrical, security, and entertainment management system including centralized audio/video wiring and distribution; xe2x80x9cadvancedxe2x80x9d phone and computer LAN wiring and systems; security systems; smart HVAC systems; and automated lighting and other automated appliances.
Many different powerline protocols have been used for home automation lighting and device/appliance control. These protocols communicate between transmitters and receivers by sending and receiving signals over existing power line wiring that are used to power the devices. More specifically, these protocols use signals via 110/120 volt, 60 cycle, electrical wiring to transport messages between devices connected to the wiring for receiving electrical power. Most homes have three wires that feed the electrical system from an electrical panel or load center. Two of the three wires each include a hot (110/120 volt leg), and the third is a neutral line. Both 110/120 volt legs together with a neutral line provide a 220/240 volt source to power 220/240 volt appliances such as a dryer or an oven. Each of the 110/120 volt legs power items such as lights and outlet plugs via one of the two hot 110/120 volt legs and the neutral line. Because most homes are wired such that 220/240 volt potential is brought into the breaker panel and then split into two phases of 110/120 volts each, the signals from one device are transmitted onto one phase and have to travel all the way out to the pole transformer (utility company transformer) to couple across to the other phase. The amplitude of the signal on the other phase may therefore be greatly reduced due to signal attenuation. In other words, the two 110/120 volt legs are only connected at the transformer outside of the home. However, sometimes the distance that the signal must travel from one 110/120 volt leg to the utility transformer back to the home via the second 110/120 volt leg is too great and the signal attenuated.
Current approaches to couple both 110/120 volt legs use a phase coupler that resides inside of the electrical distribution panel but requires special wiring into the panel through the lugs of a circuit breaker. This solution is not easily done by the average homeowner and usually necessitates an electrician to connect the phase coupler. In addition, many of the circuit breakers used for connecting the phase coupler are not designed for multiple conductors or are not sized to protect the phase coupler, thus the phase coupler is not UL compliant and does not conform to the National Electric Code (NEC).
Accordingly, it would be desirable and advantageous to provide an apparatus for allowing signal communication between two 110/120 volt legs that is low in cost, both for manufacture and installation, and which eliminates a need for an experienced electrician to couple the two phases for signal communication therebetween while maintaining the AC power isolation between them. It is also desirable that such an apparatus be UL compliant and conforms to the National Electric Code upon installation.
The above discussed and other drawbacks and deficiencies are overcome or alleviated by a phase coupler for operable communication between at least two phases of an electrical distribution system while maintaining power isolation between the phases comprising: a band pass filter circuit connected to the at least two phases and configured to transfer a signal having a predetermined frequency or frequency range from a first phase to a second phase; a first terminal in operable communication with the circuit and the first phase; a second terminal in operable communication with the circuit and the second phase; a third terminal in operable communication with the circuit and a neutral line of the electrical system; and a housing configured to enclose said circuit and provide for operable electrical connection between said first, second and third terminals and corresponding outside conductors.